This invention relates to an apparatus and method for conditioning air-entangled yarn. The invention has particular application in processing relatively high denier, multifilament yarns, such as carpet yarn, that are delivered from a yarn manufacturer or other processor with pre-inserted crimp. When used to manufacture carpets, the yarn is processed to form differing, complementary colors that are intended to provide to the carpet a blended, muted color effect.
Often, such yarns are “tacked” or “interlaced” during initial processing to make the yarn more manageable and easy to handle. These terms, used herein interchangeably, refer to any one of several processes by which the multifilaments are locked together at intervals. The process often includes the use of short-interval blasts of high-pressure air sufficient to entangle short lengths of the yarn, referred to herein as “interlace nodes.” While this process does increase the coherence of the yarn and thus aids processing during the crimp-inserting process, it has been observed that when processed in this manner, carpets tufted from such yarns have a somewhat harsh appearance, where the varying blended colors of the yarn are more distinct and less muted than desired. Particularly when an additional entangling process is used to add further loft and bulk to the yarn, the existence of many closely-spaced interlace nodes acts to restrict the degree of additional bulk that can be added to the yarn and impairs the ability to achieve the fullest possible color blending.
The method and apparatus according to the method disclosed and claimed in this application provides a simple and effective means of removing and/or loosening a sufficient number of the interlace nodes to allow the yarn to assume a more bulked, bloomed condition wherein the crimp of the individual filaments is allowed to position the filaments in a greater, more varied, three-dimensional randomized arrangement. The process is generally referred to as “conditioning” the yarn to render it more suitable for its end use without removing the twist or breaking filaments.